Making double-walled vacuum vessels.



R. BURGER. MAKING DOUBLE WALLED VACUUM VESSELS.

APPLICATION FILED JAN. 5, 1009.

Patented Apr. 20

UNITED STATES PATENT OFFICE REINHOLI) BURGER, OF BERLIN, GERMANY.

MAKING DOUBLE-WALLED VACUUM VESSELS.

Specification of Letters Patent.

Application filed January 5, 1909.

To all whom it may concern:

Be it known that I, ltnmuoLn BURGER, a subject of the German Emperor, residing at Berlin, German have invented a certain new and usefu Improvement in Making Double-Valled Vacuum Vessels, of which the following is a specification.

The invention relates to the manufacture of double walled glass vacuum vessels, such as bottles, and consists broadly in the process hereinafter described and comprising the steps more particularly pointed out in the claims.

In the accompanying drawings which are all longitudinal sectional views-Figure 1 shows separately the glass 0 linder which ultimately forms the outer wall of the bottle. Fig. 2 shows separately the glass 0 linder which ultimately forms the inner wal of the bottle. Fig. 3 shows the cylinder of Fig. 2 placed within the cylinder of Fig. 1, andthe supporting-plugs in place between the walls. F' 4 showsthe two cylinders connected oxiIy at the end of the neck or mouth of the now double walled vessel. Fig. 5 shows the same with one of the tubular pro'ections closed. Fig. 6 shows the complete vessel with both tubular projections closed after exhaustion of the space between the double walls.

Similar letters of reference indicate like .parts.

' the shape illustrated in Fig. 1, inwhich case,

the u per portion B is cut off on the line (1,0, in or or to produce a cylinder of the desired shape hav' an 0 en end at Q and a rounded bottom on at The glass cylinder E which is of less diameter than cylinder A. and is to form the inner wall of the vacuum" vessel, is usually received from the glass blowers in the siege illustrated in Fig. 2, that is, with a long y portion F and an 0' on neck G.

Upon the rounded bottom 0 of t e outer cylinder A, I form. two small projectin' tubes H, I. I then place the cylinder E wit the cylinder A, as shown in Fig. 3, and in any suitable way introduce into the space between said cylinders, bodies or plu s J, pref.

erably made of asbestos paper OIOfiIGI' yield ing heat insulating material. Said plugs may be attached to. the surface of the inner cylinder E in any suitable manner, such for between said cylinders: t

Patented April 20, 1900.

Serial No. 470,864.

instance, in the way set forth in U. S. Letters Patent N 0. 888,783, granted tome May 26 1908, before the said cylinder E- is inserted into the cylinder A, or by adhesion; or they may be inserted into the s ace between the cylinders after said cylinilers are put together and then retained in place by engagement with the walls. For convenience in handling and s acing, they may be connected b a ring K 0 Wire or cord. A lip L may also be formed at the open end of the neck of cylinder E, if desired. The two cylinders are next fused together at their months, as shown in Fig. 4, and suitably molded to shape, thus roducing a double walled vessel. In order to fill the pores of the glass, 8. silvering solution or other suitable coating may be introduced through one of said projections into the space between the walls, and a coat ing of silver or other material thus applied. One of the projections, as I, is then sealed, Fig. 5, and substantially a vacuum is produced in the said space by any suitable device applied to the remaining pro ection H. The last named projection is then sealed, thus completing t e vessel, as shown-in Fig. 6.

I claim:

' 1. The process of making glass vacuum vessels which consists in, first, placing within a glass cylinder closed at one end and open at the o posite end and havin an opemng in said c osed-end, a second cy der of less diameter 0 en at one end and closed at the other en so that a'space will be formed between said cylinders andintroducing supporting bodies into said space: second, fusing said cylinders together at their open ends: third, producing substantially a vacuum in said intermediate space, and fourth, sealing the o ening in said outer cylinder.

2. lhe process of making glass vacuum vessels which consists in, first, forming on the closed end of a glass cylinder, open at the opposite end, a tubular projection: second, 1nserting in said cylinder a second cylinder of less diameter open at one end and closed at the other end, so that. a space will be formed ird, insertingusupporting bodies in said space: fourth, sing said cylinders together at their open ends:

fifth, producing substantially a vacuum in said intermediate space, and sixth, sealing said tubular projection.

3. The rocess of making glass vacuum vessels whlch consists in, first, forming on the closed end of a glass cylinder, open at the opposite end, two tubular projections: second, inserting in said cylinder a second cylinder of less diameter open at one end and closed at the other, so that a space will be formed he- 5 tween said cylinders: third, inserting supporting bodies in said space: fourth, fusing said cylinders together at their open ends: fifth, introducing a coating solution into said space: sixth, closing one of said tubular projections: seventh, producing substantially a 10 vacuum in said s ace, and eighth, closing said remaining tu ular ro'ection.

In testimony whereo I ave aflixed my signature in presence of two witnesses.

. REINHOLD BURGER. Witnesses:

' WOLDEMAR HAUPT, HENRY HASPER. 

